Rotary kiln lining



oct. 7, 1941;

' c. J. scovRoN i 2,258,518A

ROTARY KILN LINING Filed Jan. 11, 1940 2 sham-Sheena 4 Patented Oct. 7,1941 ROTARY KILN, LINING Charles J. Scovron, Donora, Pa., assignor toThe American Steel and Wire Company of New Jersey, a corporation of NewJersey Application January 11, 1940, Serial No.1313',449 1 Claim. (Cl.263-32) This invention relates to improvements in linings for rotarykilns and the like.

In the processing of certain materials, such as low grade ores,residues, etc., they are sometimes heated and rotated in kilns fordriving off and collecting the contained volatile substances by what isknown as the Waelz process.

' Certain residues treated in the Waelz kiln are highly viscous incharacter and tend to follow the rotary travel of 'the kiln in a masswithout completely releasing the contained volatiles.

It is an object of the present invention to provide a lining for such akiln which will impart increased agitation to the residue or materialfor completely releasing the volatile substances contained therein. o v

Another object is to provide a lining which will break up the mass ofthe `material to prevent molding thereof throughout the kiln, and toeffect a positive advance or feed of the material through the kiln.

A further object is to provide a lining'of the character stated formedof standard brickA incorporating the aforementioned features therein ina simple and economical construction which may be readily applied to akiln.

Additional objects and advantages will become apparent from thefollowing description taken in connection with the accompanying drawingswherein:

' Figure 1 is a longitudinal sectional view of a portion of a rotarykiln showing the lining of my invention; l

Figures 2 and 3 are cross-sections taken on the lines II-II and ITI-IHof Figure 1, respectively; and

Figure iris a schematic developed view of the brick layout of thelining.

Referring to the drawings, 2 designates the outer cylindrical shell orbody of a rotary kiln, as for example. a Waelz kiln for the recovery ofsage or roll extending through the kiln, and to positively feed oradvance the broken material through the kiln.

For these purposes, the generally cylindrical refractory brick lining ofthe kiln is provided with a plurality of spaced longitudinal inwardlyextending projections or ribs 3, preferably formed by double rows ofbricks 4 of greater depth than the bricks 5 'comprising the majorportion of the lining.

'Ihe ribs or projections 3 are spaced circumferentially of the kiln,providing smooth lining portions 6 therebetween, which portions haveproper ex'tent between the ribs 3 to produce the desired action of thematerial as hereinafter described.

Connecting and extending between the projections or ribs 3, I provide aseries of transverse feed ribs or projections 1, preferably composed ofdouble rows of bricks 8 of greater depth than the bricks 5, said feedribs extending inwardly from the smooth brick portions 6. Ribs 1 arearranged i-n staggered relation longitudinally of the kiln, whereby thesaid ribs 'l of a portion 6 are staggered with respect to those of thenext adjacent portions 6.

In operation, the longitudinal ribs 3 impart a tumbling movement to thematerial in the rotating kiln, the circumferential width of the smoothlining portions 6 between ribs 3 preferably exceeding the correspondingdimension of the said ribs, and being of sufficient width to permittravel of the residue longitudinally of zinc, cadmium, lead, etc. fromretort or furnace residues. Said kiln is designed to rotate about itslongitudinal axis in a slightly inclined position,

whereby the contents may travel throughout the kiln during itsoperation. s

As stated, certain residues, such as those from zinc furnaces, arehighly viscous` and in order to properly treat the same in the kiln, itis necessary to prevent sliding thereof along the kiln 1ining, and toprevent mass formation of the residue.

I have found that the best results may be obtained Aby agitating theresidue, breaking it up to prevent mass formation thereof into a sauthekiln Without clogging or packing between ribs.

The` tumbling mass of material is engaged at intervals by the feed ribs1, whereby the same is severed into sections or portions. The ribs 1 ofeach lining portion 6 will serve the mass of the material' on saidportion, and the severed material will again be severed by the ribs l ofthe next portion 6 which the mass engages, and so on, to continuallymaintain the material in broken condition. 4

Also, the series of staggered feed ribs 'l functions as a multiple screwto feed the material being treated longitudinally of the kiln, whichaction together with the inclination of the kiln, provides a positivetravel or feed of the material through the kiln.

As clearly shown in the drawings, the several bricks I, 5 and 8 are allof the standard form employed in the construction ofcylindrical lin'-ings, no special shape or configuration of bricks being necessary forforming the projecting ribs 3 and 1. 'I'he bricks I, 5 and 8 compriseequal segments of the lining whereby they are readily laid in the brokenjoint pattern generally em- Y ployed in brick work. The developed layoutof the present invention in Figure 4 clearly shows the ribs orprojections 3 and 1, the same being emphasized by the shading.

A rotary kiln employing a, lining of the character stated will providefor complete and emcient agitation and breaking-up of the material beingtreated, thereby continually exposing new surfaces or portions of thematerial for release of the contained volatile substances.

Various changes and modifications are contemplated within the scope ofthe following claim.

I claim:

A cylindrical refractory lining for inclined rotary kilns of the Waelz,type including a plurality of ribs extending longitudinally throughoutthe kiln, said ribs extending inward beyond the lining proper and havingprojecting radial faces, said ribs being spaced circumferentially of thelining to permit tumbling agitation of a mass or material in the kiln bythe lining portions between said ribs, and a plurality ofcircumferentially disposed ribs extending radially inward bef yond thelining proper and transversely of the lining portions between and atright angles to the longitudinal ribs, the transverse ribs beinglongitudinally staggered between adjacent longitudinal ribs for severingand advancing the mass in the kiln, said lining and ribs being composedof refractory brick, the brick of the ribs having a greater radialdimension than the bricks of the lining proper, and the'rib and liningbricks being laid in regular broken joint pattern throughout the entirelining.

CHARLES J. SCOVRON.

